How is symbiosis defined?

Symbiosis is defined as a close ecological relationship between two or more different species. This definition highlights the nature of interactions that can occur in various forms, such as mutualism, commensalism, and parasitism, all of which involve significant interactions between different organisms in an ecosystem. The term "close" emphasizes the ongoing and often long-term nature of these relationships, which can have profound effects on the participating species. Understanding symbiosis is crucial in biology because it illustrates how different organisms can coexist and interact in their environments, influencing biodiversity and ecosystem dynamics.